Structural rejuvenation in a Zr-based bulk metallic glass via electropulsing treatment

Abstract

Structural rejuvenation is a fascinating issue of bulk metallic glasses (BMGs). In this paper, we use the electropulsing treatment (EPT) to rejuvenate the atomic packing in a Zr45(Cu4.5/5.5Ag1/5.5)48Al7 BMG, which remains amorphous after undergoing fast heating and cooling. It is found that the voltages less than 110 V have little rejuvenation effect on BMGs. However, the discharging at 130 V greatly reduces the density, modulus, and hardness while generating more excess free volume and enhancing the β-relaxation. The changes in properties of EPT samples are almost consistent with the variations of total content and average size of free volume. Our work provides an efficient way to alter the structure and properties of BMGs.